Hi, "openCV" might be a good start for Object Recognition/Detection and Rtabmap uses appearance based localization and Odometry, might be of interesst for you. There should also be interessting research in regards to "path planning" specially when it comes to crowded spaces where the situation changes fast. Crowded spaces should be a good search term as it complicates nearly everything, thus thinking beyond alghorythms should be found there. A big topic of interesst would be self learning locomotion in robot kinematics. Although its not strictly robotics but "chatbots" and speech recognition/interpretation("what does the spoken sentence actually mean") should as well be a hot topic for AI as speech is way to complex for alghorythms, see google translates poor quality.

Thank you for your opinion :)